class_docstr: Dummy Problem for running the policy.
code: def num_actions(self):
      return self._ttt_env.action_space.n
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import gym
  from gym import spaces
  from gym.utils import seeding
  import numpy
  from tensor2tensor.data_generators import problem
  from tensor2tensor.layers import modalities
  from tensor2tensor.rl import gym_utils
label_desc: Use image node_id 3 for calling the DummyPolicyProblemTTT obj's underlying member method code with example usage: obj.num_actions() and returns: self